Explanation: Comet NEAT (Q4)
was quite photogenic earlier this month.
Although the head and part of the
tails of Comet C/2001 Q4 (NEAT) were
visible to the unaided eye, the best views of the
colorful tail were revealed only later by
cameras
able to expose for long periods.
A human eye can accumulate light for up to 1/10th of a second,
as opposed to the
above camera image,
which used an exposure of thirty seconds on May 8.
Visible is a long blue
ion tail, a blue
coma surrounding the comet's
nucleus,
and a shorter but brighter sunlight reflecting
dust tail.
Q4 is dropping more from easy
visibility each day as it recedes from both the Earth and the Sun.
Another separate naked-eye comet,
Comet LINEAR (T7),
should remain bright into June.